Centrifugal machine.



f A. J. ERICSSON.

GENTRIPUGAL MACHINE.

APPLICATION FILED PEB. 17, 1904.

PATENTED OCT. 2'5, 1904.

No MODEL.

Patented October 25, 1904.

PATENT Trice.,

ANDERS JOHAN ERICSSON, OF STOCKHOLM, SVEDEN, ASSIGNOR TO AKTIEBOLAGET SEPARATOR, OE STOCKHOLM, SWEDEN.

CENTRIFUGAL MACHINE.

SPECIFICATION forming part of Letters Patent'No. 773,489, dated October 25, 1904. Application filed Februarj`l7, 1904. Serial No. 194,055, (No model.)

in Centrifugal Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and A to letters of reference marked thereon, which form a part of this specification.

By the centrifugation of liquid substances containing; more or less finely-divided solid matters suspended therein the main difficulty consists in continuously removing in a convenient and effective manner the solid ingredients separated, which solids being somewhat heavier than the liquid stratify along the periphery of the rotary bowl.

In centrifugal separators of the kind in question perforated bowls are usually employed, by means of which the liquid is conducted away through the perforations of the bowl, while the solid substances are scraped oi the inner wall of the bowl and continuously removed from the bowl through an opening in the bottom. lf the substances suspended in the liquid, however, are verynely divided they pass, actuated by the centrifugal force, with the liquid out through the perforations in the bowl, owing to the fact that the perforations, for practical reasons, in order to avoid being choked, cannot be made too fine, and consequently only the coarser solid ingredients will be separated from the liquid. A perfect centrifugal separation of liquids containing suspended substances in a very finely-divided condition can therefore not be effected in such centrifugal separatingapparatus. Of late years the bowl has therefore been made whole-vl. e., without perforations. In such a centrifugal separating apparatus two hollow cylinders, practically speaking, are formed during centrifugal separating, of which cylinders the inner one consists of the specific lighter portion of the mixture, the liquid, while the outer one consists of the heavier portion, the solid ingredients, which according to their inherent specific weight stratify in a more or less thick layer at the periphery of the bowl. Itis thus necessary in such centrifugal separating apparatus to continuously remove the separated solid ingredients without the liquid accompanying them. As this cannot be effected outward without great difiiculty, the solid ingredients stratified at the periphery must be brought inward through the concentric layer of the liquid near the center in order to be carried out in some way within the same from the rotary bowl. Asolution of this problem has been attempted in such manner, for instance, that the liquid compound has been introduced in a separate smaller bowl mounted eccentrically in the rotating' bowl, in which case the solid ingredients deposit themselves on the` most eccentric portion of the inner bowl, whence they are subsequently moved forward by means of rotatingscrapers to an outlet at the opposite side of the bowl. (See United States Patent No. 677,926.)

This invention relates to a device for continuously moving the solid ingredients stratiiied concentric along the Whole periphery of the rotary bowl through the layer of liquid to a point within the same nearer the center of the bowl, whence the said ingredients are continuously carried away.

The device is illustrated in the accompanying drawings, in which- Figure l shows a vertical section of a centrifugal separating' apparatus provided with the device in question, while Eig. 2 shows the centrifugal separating apparatus in plan with the cover removed, partly in section.

The centrifugal bowl consists of an upper part or cover a and an under part or bottom I), screwed together in the usual manner. The driving-shaft Z of the bowl, which is enlarged at the top to a liange CZ', 'riveted to the bottom of the bowl, is made hollow and within the same massive shaft e passes up. Above the bottom of the bowl a shell c is mounted, through which the shaft e passes and which is shaped at the top like a flange, which is provided with cogs on the outside. On the top of the shaft e, projecting above the shell c c, cross-piecef is mounted, to the ends of which cross piece short downi iard.- directed shafts g f/ are attached, which shafts are secui'ed to the cross-piece by means of nuts. On these shafts ai'e situated undei' the crosspiece cog-wheels /i 7i, gearing in the cog-ring on the fixed shell c, and, further, naves fz.' a', to which are fastened a number (in the drawings four) ofscrapers of scoop or shovel shape, the concave sides of which are turned toward the direction of movement of the centrifugal bowl. 'lhe cog-wheels t, as well as the naves z', go loose on the shafts y, but are secured to each other by means of screws. Consequently when the shaft e is set in rotation with a speed either greater or less than the periphery speed of the bowl, the shafts r/ and the cog-wheels /z/ and the scraper-wheels z' 2.' mounted onA them, receive a motion relative to the bowl and at the saine time, owing to the gearing of the cog-wheels /i/ in the cog-ring on the shell c, they rotate round the shaft gy.

1n consequence hereof the scrapei's do not always touch the same point of the periphery of the bowl, but successively move along the periiiiliery, scraping off every time in this movement a portion of the solid substances stratified on the wall of the bowl. During the rotation of the scrai'ier-wheels round their own shafts the solid substances carried up by the scrapers are transported transversely through the layci' of liquid to the centei' of the bowl. At the commencement of this movement the scraper is thus moved toward the direction of rotation of the bowl, in consequence of which the solid substances are pressed against the concave inside of the scrapei'. As soon as the scraper has turned one hundred and eighty degrees from the po sition where it touches the wall of the bowl, the centrifugal force created in consequence of the rotation of the bowl acts on the contents of the scraper, and these contents should accordingly, providing` nothing be done to hinder this, be again thrown out towai'd the periphery of the bowl or accompany the scraper on its return movement toward the periphery. lt is consequently necessary to catch the solid substances in some way and carry them oli' just when the scraper occupies its position nearest the center of the bowl. This is effected, according to this invention, in the following manner: Immediately under the shovel-wheels there is a horizontal partition closing` against the wall of the bowl, which partition is provided with a central opening, the radius of which is equally large as or a little larger than the distance from the line of center of the bowl to the naves of the scraperwlieels. 1n consequence hereof the solid su bstances taken up in the scraper will, as soon i center of the bowl, owing to the action of the l as this one occupies its position nearest the i l centrifugal force, be loosened fi'om the scraper, l

and thereafter they are further, in consequence of the same force and their gravity, thrown obliquely downward through the central opening (sec the arrow in Fig. l) to the chamber under the partition t, where there is no liquid, and thence through an opening in the wall of the bowl out to a suitable receptacle.

The bowl is provided in the usual manner with a spreader l, placed under the feed-opening, whereby the liquid compound continuously fed into the bowl is thrown out toward the wall of the bowl, which it follows until it stratilies in the lower portion of the bowl, as mentioned above, in an inner layer of liquid and an outer layer ofy solid substances separated from the liquid.

In the cover of the bowl a hole m (or several holes) is located, forming outlet for the liquid, theiinterior level of which coincides with the outer edge of the said hole. In Fig. 2 the level of the liquid is denoted by the dotted circle n.

.l claimm 1. In a centrifugal machine, the combination with the rotary bowl having solid walls, of means located within the bowl and working along' its entire periphery for conveying the solid mattei' stratified on the walls to a point nearer the center lineof the bowl, said means being constructed to rotate at a speed diiferent from that of the bowl and to rotate around its own axis in a direction different from the i direction of rotation of the bowl.

2. Ina cen trifugal machine, the combination with the rotary bowl having solid walls, hollow shaft and an outlet between the walls and the shaft, of a second shaft projectingthrough said hollow sliaftinto the interioi' of the bowl and constructed to be rotated at a speed different from that of the bowl, means connecti ed to said second shaft within the bowl for conveying the solid matter stratified on the walls to said outlet, said means operating along the entire periphery of the bowl and rotating with said second shaft, and means for imparting rotation to said conveying means around its own axis and in a direction different from the direction of rotation of the bowl.

3. ln a. centrifugalmachine, the combination with the rotary bowl having solid walls, hollow shaft and an outlet between the walls and the shaft, of a second shaft projecting into the intei'ioi' of the bowl through said hollow shaft and constructed to be rotated at a speed different from that of the bowl, means connected to said second shaft within the bowl for conveying the solid mattei' stratified on the walls lto said outlet, said means operating along the entire periphery of the bowl and rotating with said second shaft, and means located on the inner surface of the bowl for imparting rotation to said conveying means around its own axis and in a direction different 'from the direction of rotation of the bowl.

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4. In acentrifugal machine, the combination with the rotary bowl having solid walls` hollow shaft and an outlet between the walls and the shaft, of a second shaft projecting through said hollow shaft into the interior of the bowl and constructed to be rotated at a speed different from that of the bowl, a horizontal flange rigidly connected to said second shaft within the bowl, a scraper-wheel journaled in said fiange and operating along the entire periphery of the bowl for conveying the solid matter stratified on the walls to said outlet.

5. In a centrifugal machine, the combination with the rotary bowl having solid walls, hollow shaft and an outlet between the walls and the shaft, of a second shaft projecting through said hollow shaft into the interior of the bowl and constructed to be rotated at a speed different from that of the bowl, a horizontal flange rigidly connected to said second shaft within the bowl, a scraper-wheel journaled in said flange and operating along the entire periphery of the bowl for conveying the solid matter stratified on the walls to said outlet, and means for rotating said scraper-wheel around its own axis in a direction different from the direction of rotation of the bowl.

6. In a centrifugal machine, the combination with the rotary bowl having solid walls, hollow shaft and an outlet between the walls and the shaft, of a second shaft projecting through said hollow shaft into the interior of the bowl and constructed to be rotated at a speed different from that of the bowl, a horizontal fiange rigidly connected to said second shaft within the bowl, a plurality of scraper-wheels journaled in said flange and operating along the entire periphery of the bowl for conveying the solid matter stratified on the walls to said outlet, and means located on the inner surface of the bowl for imparting rotation to said scraper-wheels around their own axes.

7. In acentrifugal machine, the combination with the rotary bowl having solid walls, hollow shaft and an outlet between the walls and the shaft, of a second shaft projectingthrough said hollow shaft into the interior of the bowl and constructed to be rotated at a speed different from that of the bowl, a horizontal fiange rigidly connected to said second shaft within the bowl, a plurality of scraper-wheels journaled in said Hange and operating along the entire periphery of the bowl for conveying the solid matter stratified on the walls to said outlet, and means located on the inner surface of the bowl for imparting rotation to said scraper-wheels around their own axes and in a direction different from the direction of rotation of the bowl.

8. In a centrifugal machine, the combination with the rotary bowl having solid walls, hollow shaft and an outlet between the walls and the shaft, of a second shaft projecting through said hollow shaft into the interior of the bowl and constructed to be rotated at a speed dierent from that of the bowl, a-horizontal flange rigidly secured to said second shaft within the bowl, a plurality of scraper-wheels journaled in said flange and operating along the.

entire periphery of the bowl for conveying the solid matter stratified on the walls to said outlet, pinions secured to said scraper-wheels, and a gear-wheel secured to the bowl and meshing with said pinions for imparting rotation to the scraper-wheels around their own axes.

9. In acentrifugal machine,the combination with the rotary bowl having solid walls, of a horizontal partition-wall within the bowl said partition-wall having an opening' concentric with the bowl, and communicating with the exterior of the bowl, a plurality of scraperwheels arranged within the bowl and protruding over said opening for conveying the solid matter stratified on the walls to said opening, and means for rotating said scraper-wheels around their own axes.

l0. In a centrifugal machine, the combination with the rotary bowl having' solid walls, of a horizontal partition-wall within the bowl, said partition-wall having an opening concentric'with the bowl and communicating with the exterior of the bowl, a plurality of scraperwheels arranged within the bowl, a plurality of scraper-wheels arranged within the bowl and protruding over said opening for conveying the solid matter stratified on the walls to said opening, means for rotating said scraperwheels around the axis of the bowl and at a different speed from that of the bowl, and means for rotating the scraper-wheels around their own axes in a direction different from the direction of rotation of the bowl.

411. Ina centrifugal machine, the combination with the rotary bowl having solid walls, an outlet for the liquid and an outlet for the solid matter, the last-named outlet being located between the first-named outlet and the centerline of the bowl, of means operating along the entire periphery of the bowl for conveying the solid matter stratified on the walls to said outlet for the solid matter, said means comprising a plurality of scraperwheels arranged at equal distance from the center line of the bowl and protruding over said outlet for the solid matter.

l2. In a centrifugal machine, the combination with the rotary bowl having solid walls, an outlet for the liquid and an outlet for the solid matter, the last-named outlet being located between the first-named outlet and the center line of the bowl, of means operating along the entire periphery of the bowl for conveying the solid matter stratified on the walls to said outlet for the solid matter, said means comprising a plurality of scraperwheels arranged in the same plane and at equal distance from the center line of the bowl and protruding over said outlet for the solid matter.

13. In a centrifugal machine, the combina- IOO tion with the rotary bowl having` solid walls,

an outlet for the liquid and an outlet for the solid matter, the last-named outlet being,` located between the first-named outlet and the center line of the bowl, of means operating along the entire periphery of the bowl for conveyix'igl the solid matter stratilied on the walls to said outlet for the solid matter, said means colinprising' a plurality of scraperwheels arranged in the same plane and at equal distance from the center line of the bowl and protruding' over said outlet for the solid matter, means for rotating, the scraperwheels around the center line ol" the bowl at a speed dilferent from that of the bowl, and I5 means for rotatinggl the scraper-wheels around. their own axes in a direction opposite to the direction of rotation of the bowl.

ln testimony that l claim the foregoing as' iny invention l have signed inynalne in pres- 2O ence of two subscribing witnesses.

ANDERS JOHAN ERICSSON Witnesses:

Tri. WAwiarNsiiY, L. KALLENBERG. 

